Multilayer ceramic electronic component

ABSTRACT

A multilayer ceramic electronic component includes a ceramic body including a capacitance formation portion including a dielectric layer and first and second internal electrodes with the dielectric layer interposed therebetween; and first and second external electrodes disposed on the first and second surfaces of the ceramic body, respectively, and including first and second base electrodes connected to the first and second internal electrodes and first and second conductive layers disposed to cover the first and second base electrodes. When a thickness of the first and second conductive layers in a central portion of the first and second surfaces of the ceramic body is a, and a thickness of the first and second conductive layers at an end of the capacitance formation portion is b, b/a is 0.07 or more.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a continuation application of U.S. patentapplication Ser. No. 16/838,592 filed on Apr. 2, 2020, which claims thebenefit of priority to Korean Patent Application No. 10-2019-0116144filed on Sep. 20, 2019, in the Korean Intellectual Property Office, thedisclosures of which are incorporated herein by reference in theirentirety.

TECHNICAL FIELD

The present disclosure relates to a multilayer ceramic electroniccomponent.

BACKGROUND

In recent years, with the trend for miniaturization of electronicproducts, multilayer ceramic electronic components are also required tobe miniaturized while having high capacity. In accordance with thedemand for miniaturization and high capacity in multilayer ceramicelectronic components, external electrodes of the multilayer ceramicelectronic components are also becoming thinner.

Conventionally, glass, a base resin, an organic solvent, and the likehave been mixed with a conductive metal to prepare an external electrodepaste, and a dipping method sintering a ceramic body after applying theexternal electrode paste to both end surfaces of the ceramic body hasbeen used to form the external electrode.

However, when the external electrode is formed by the dipping method, anexternal electrode of an outermost region may be thinly formed, therebydeteriorating corner coverage performance. In addition, it is easy topermeate foreign materials such as moisture, or the like, which is amajor cause of the deterioration of product quality due to deteriorationof moisture resistance.

An aspect of the present disclosure is to provide a multilayer ceramicelectronic component that may improve moisture resistance by blocking amoisture permeation path by improving corner coverage performance of anexternal electrode.

According to an aspect of the present disclosure, a multilayer ceramicelectronic component includes a ceramic body including a capacitanceformation portion including a dielectric layer and first and secondinternal electrodes stacked in a stacking direction with the dielectriclayer interposed therebetween, and having a first surface and a secondsurface opposing to each other in a first direction, a third surface anda fourth surface opposing to each other in a second direction, and afifth surface and a sixth surface opposing to each other in a thirddirection which is the stacking direction; and first and second externalelectrodes disposed on the first and second surfaces of the ceramicbody, respectively, and including first and second base electrodesconnected to the first and second internal electrodes, respectively, andfirst and second conductive layers disposed to cover the first andsecond base electrodes, respectively. A ratio ‘b/a’ is 0.07 or more,where a thickness of the first and second conductive layers in a centralportion of the first and second surfaces of the ceramic body is ‘a’, anda thickness of the first and second conductive layers at an end of thecapacitance formation portion is ‘b’.

BRIEF DESCRIPTION OF DRAWINGS

The above and other aspects, features, and advantages of the presentdisclosure will be more clearly understood from the following detaileddescription, taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 is a schematic perspective view illustrating a multilayer ceramicelectronic component according to an embodiment of the presentdisclosure;

FIG. 2 is a schematic perspective view illustrating a ceramic body of amultilayer ceramic electronic component according to an embodiment ofthe present disclosure;

FIG. 3 is a cross-sectional view taken along line I-I′ of FIG. 1 ;

FIG. 4 is an enlarged view of region A of FIG. 3 ; and

FIG. 5 is an enlarged view of region B of FIG. 3 .

DETAILED DESCRIPTION

Hereinafter, embodiments of the present disclosure will be described indetail with reference to the accompanying drawings. The presentdisclosure may, however, be exemplified in many different forms andshould not be construed as being limited to the specific embodiments setforth herein. Rather, these embodiments are provided so that thisdisclosure will be thorough and complete, and will fully convey thescope of the disclosure to those skilled in the art. In the drawings,the shapes and dimensions of elements may be exaggerated for clarity.Further, in the drawings, elements having the same functions within thesame scope of the inventive concept will be designated by the samereference numerals.

In the drawings, irrelevant descriptions will be omitted to clearlydescribe the present disclosure, and to clearly express a plurality oflayers and areas, thicknesses may be magnified. The same elements havingthe same function within the scope of the same concept will be describedwith use of the same reference numerals. Throughout the specification,when a component is referred to as “comprise” or “comprising,” it meansthat it may include other components as well, rather than excludingother components, unless specifically stated otherwise.

In the drawings, an X direction may be defined as a first direction, anL direction or a length direction, a Y direction may be defined as asecond direction, a W direction or a width direction, and a Z directionmay be defined as a third direction, a T direction and a thicknessdirection.

Hereinafter, a multilayer ceramic electronic component according to anembodiment of the present disclosure will be described in detail withreference to FIGS. 1 to 5 .

Referring to FIGS. 1 to 5 , a multilayer ceramic electronic componentmay include a ceramic body 110 including a capacitance formation portionincluding a dielectric layer 111 and first and second internalelectrodes 121 and 122 disposed to be stacked in a third direction (theZ direction) with the dielectric layer 111 interposed therebetween, andincluding first and second surfaces S1 and S2 opposed in a firstdirection (the X direction), third and fourth surfaces S3 and S4 opposedin a second direction (the Y direction), and fifth and sixth surfaces S5and S6 opposed in a third direction (the Z direction); and first andsecond external electrodes 131 and 132 disposed on the first surface S1and the second surface S2 of the ceramic body 110, respectively, andincluding first and second base electrodes 131 a and 132 a connected tothe first and second internal electrodes 121 and 122 and first andsecond conductive layers 131 b and 132 b disposed to cover the first andsecond base electrode 131 a and 132 a.

In this case, when a thickness of the first and second conductive layers131 b and 132 b in a central portion of the first surface S1 and thesecond surface S2 of the ceramic body 110 is a, and a thickness of thefirst and second conductive layers 131 b and 132 b at an end of thecapacitance formation portion is b, b/a may exceed 0.07. The thickness‘a’ of the first and second conductive layers 131 b and 132 b may mean alength of the first and second conductive layers 131 b and 132 b in afirst direction (the X direction)in a central portion of the firstsurface S1 and the second surface S2 of the ceramic body 110. Inaddition, the thickness ‘b’ of the first and second conductive layers131 b and 132 b may mean a length of the first and second conductivelayers 131 b and 132 b in a first direction (the X direction) at an endof the capacitance formation portion of the first surface S1 and thesecond surface S2 of the ceramic body 110.

By making the ratio b/a exceed 0.07, corner coverage performance ofexternal electrodes may be improved.

In an embodiment of the present disclosure, a ceramic body 110 mayinclude a capacitance formation portion including a dielectric layer 111and first and second internal electrodes 121 and 122, a margin portion112 disposed on both surfaces (e.g., the third and fourth surfaces S3and S4) of the capacitance formation portion in a second direction (theY direction), and a cover portion 113 disposed on both surfaces (e.g.,the fifth and sixth surfaces S5 and S6) of the capacitance formationportion in a third direction (the Z direction).

Although a specific shape of the ceramic body 110 is not particularlylimited, as shown, the ceramic body 110 may be formed in a hexahedralshape or a shape similar thereto. Due to shrinkage of ceramic powdercontained in the ceramic body 110 during a firing process, the ceramicbody 110 may have a substantially hexahedral shape, although not ahexahedral shape having perfect straight lines. The ceramic body 110 mayhave first and second surfaces S1 and S2 opposing each other in alongitudinal direction (the X direction), third and fourth surfaces S3and S4 connected to the first and second surfaces S1 and S2 and opposingeach other in a width direction (the Y direction), and fifth and sixthsurfaces S5 and S6 connected to the first and second surfaces S1 and S2,connected to the third and fourth surfaces S3 and S4 and opposing eachother in a thickness direction (the Z direction).

The ceramic body 110 may be formed by alternately stacking a ceramicgreen sheet on which a first internal electrode 121 is printed and aceramic green sheet on which a second internal electrode 122 is printedin a thickness direction (the Z direction).

The capacitance formation portion may be formed by alternately stackinga dielectric layer 111 and internal electrodes 121 and 122 in a thirddirection (the Z direction). A plurality of dielectric layers 111forming the capacitance formation portion may be in a sintered state,and boundaries between adjacent dielectric layers 111 may be integratedsuch that they may be difficult to confirm without using a scanningelectron microscope (SEM).

According to an embodiment of the present disclosure, a raw material forforming the dielectric layer 111 is not particularly limited, as long assufficient capacitance may be obtained therewith. For example, a bariumtitanate-based material, a lead composite perovskite-based material, astrontium titanate-based material, or the like may be used.

A variety of ceramic additives, organic solvents, plasticizers, binders,dispersants, and the like may be added to powder particles such asbarium titanate (BaTiO₃), and the like, depending on the purpose of thepresent disclosure.

For example, the dielectric layer 111 may be formed by applying anddrying a slurry formed by including powder such as barium titanate(BaTiO₃) on a carrier film to prepare a plurality of ceramic sheets. Theceramic sheet may be formed by mixing ceramic powder, a binder, and asolvent to prepare a slurry, and manufacturing the slurry into a sheethaving a thickness of several μms by a doctor blade method, but is notlimited thereto.

A multilayer ceramic electronic component of the present disclosure maybe disposed such that a plurality of internal electrodes 121 and 122 aredisposed to oppose each other with the dielectric layer 111 interposedtherebetween. The internal electrodes 121 and 122 may include first andsecond internal electrodes 121 and 122 that are alternately disposed tooppose each other with the dielectric layer 111 interposed therebetween.

The first internal electrode 121 may be exposed to one surface S1 of theceramic body 110 in the first direction (the X direction), and a portionexposed to the one surface S1 in the first direction (the X direction)may be connected to a first external electrode 131. The second internalelectrode 122 may be exposed to the other surface S2 of the ceramic body110 in the first direction (the X direction), and a portion exposed tothe other surface S2 of the first direction (the X direction) may beconnected to a second external electrode 132. The first and secondinternal electrodes 121 and 122 may be electrically separated from eachother by the dielectric layer 111 disposed in a middle.

A material for forming the first and second internal electrodes 121 and122 is not particularly limited, and for example, the first and secondinternal electrodes 121 and 122 may be formed by using a conductivepaste including one or more materials of silver (Ag), palladium (Pd),gold (Au), platinum (Pt), nickel (Ni), copper (Cu), tin (Sn), tungsten(W), titanium (Ti), and alloys thereof. As a printing method of theconductive paste, a screen-printing method, a gravure printing method,or the like, may be used, but the present disclosure is not limitedthereto.

In a multilayer ceramic electronic component according to the presentdisclosure, a margin portion 112 may be disposed on both surfaces of thecapacitance formation portion in a second direction (the Y direction).The margin portion 112 may be disposed on both surfaces of thecapacitance formation portion in the second direction (the Y direction)perpendicular to the first and third directions (X and Z directions),respectively. The margin portion 112 may serve to prevent damages to theinternal electrodes due to physical or chemical stresses.

The margin portion 112 may be made of an insulating material, and may bemade of a ceramic material such as barium titanate, or the like. In thiscase, the margin portion 112 may include the same ceramic material asthat included in the dielectric layer 111, or may be made of the samematerial as the dielectric layer 111. A method for forming the marginportion is not particularly limited. For example, an area of thedielectric layer included in the capacitance formation portion may beformed to be greater than an area of the internal electrode, to form amargin area may be formed in a remaining circumferential portion exceptfor the portion of the internal electrode connected to the externalelectrode, or it may be formed by applying a slurry containing ceramicor attaching a dielectric sheet to both surfaces of the capacitanceformation portion in a second direction (the Y direction).

The multilayer ceramic electronic component according to the presentdisclosure may include a cover portion 113. The cover portion 113 may bedisposed at an outermost portion of the first and second internalelectrodes 121 and 122. The cover portion 113 maybe disposed below theinternal electrode of the lowermost portion of the body 110 and abovethe internal electrode of the uppermost portion. In this case, the coverportion 113 may be formed of the same composition as the dielectriclayer 111, and may be formed by stacking at least one or more dielectriclayers that do not include an internal electrode on an upper portion ofthe uppermost internal electrode and on a lower portion of the lowermostinternal electrode, respectively. The cover portion 113 may basicallyserve to prevent damage to the internal electrode due to physical orchemical stresses.

In the multilayer ceramic electronic component 100 according to thepresent disclosure, a first external electrode 131 and a second externalelectrode 132 may be disposed on both surfaces of the ceramic body in afirst direction (the X direction). The first external electrode 131 maybe connected to the first internal electrode 121, and the secondexternal electrode 132 may be connected to the second internal electrode122.

The first and second external electrodes 131 and 132 may include firstand second base electrodes 131 a and 132 a disposed on both surfaces ofthe ceramic body 110 in a first direction (the X direction) andconnected to the first and second internal electrodes 121 and 122,respectively, and first and second conductive layers 131 b and 132 bdisposed to cover the first and second base electrodes 131 a and 132 a,respectively.

In an example of the present disclosure, the first external electrode131 may be disposed to be extended onto the third to sixth surfaces S3to S6 in contact with the first surface S1 of the ceramic body 110, andthe second external electrode 132 may be disposed to extend to the thirdto sixth surfaces S3 to S6 in contact with the second surface S2 of theceramic body 110. Referring to FIGS. 1 and 3 , the first and secondexternal electrodes 131 and 132 may be disposed to be extended onto thefirst surface or the second surface S1 or S2 of the ceramic body 110 andon the third to sixth surfaces (S3 to S6) surfaces, respectively, incontact with the first surface or the second surface S1 or S2 of theceramic body 110. As described above, the first and second externalelectrodes 131 and 132 may be disposed to cover each corner of theceramic body 110, thereby suppressing external moisture permeation.

In an embodiment of the present disclosure, a first base electrode 131 aand a second base electrode 132 a may contain copper (Cu). The firstbase electrode 131 a and the second base electrode 132 a may contain amajority of copper, but are not limited thereto. For example, the firstbase electrode 131 a and the second base electrode 132 a may be formedusing a conductive paste including one or more materials of nickel (Ni),tin (Sn), palladium (Pd), platinum (Pt), gold (Au), silver (Ag),tungsten (W), titanium (Ti), lead (Pb), and alloys thereof, and glass.

A method of forming the first base electrode 131 a and the second baseelectrode 132 a does not need to be particularly limited, and the firstbase electrode 131 a and the second base electrode 132 a may be formedby dipping a ceramic body in a conductive paste containing a conductivemetal and glass or by printing the conductive paste on a surface of theceramic body by using a screen printing method, a gravure printingmethod, or the like. In addition, the conductive paste may be formed byapplying the conductive paste on the surface of the ceramic body ortransferring a dry film formed by drying the conductive paste onto theceramic body, but is not limited thereto. The first base electrode 131 aand the second base electrode 132 a may be formed by using theabove-described conductive paste, thereby maintaining sufficientconductivity, and increasing density of the external electrode due toadded glass, thereby increasing a plating solution, permeation of aplating solution and/or external moisture may be effectively suppressed.

A glass component included in the first base electrode 131 a and thesecond base electrode 132 a may be a composition in which oxides aremixed, but is not particularly limited, but may be one or more selectedfrom a group consisting of a silicon oxide, a boron oxide, an aluminumoxide, a transition metal oxide, an alkaline metal oxide, and analkaline earth metal oxide. The transition metal may be one or moreselected from a group consisting of zinc (Zn), titanium (Ti), copper(Cu), vanadium (V), manganese (Mn), iron (Fe) and nickel (Ni), thealkaline metal may be one or more selected from a group consisting oflithium (Li), sodium (Na), and potassium (K), and the alkaline earthmetal may be one or more selected from a group consisting of magnesium(Mg), calcium (Ca), strontium (Sr), and barium (Ba).

In an example, the thickness of the first base electrode 131 a and thesecond base electrode 132 a may be in a range of 3 μm to 13 μm. Athickness of the first base electrode 131 a and the second baseelectrode 132 a may mean a length of the first base electrode 131 a andthe second base electrode 132 a in a first direction (the X direction).The thickness may be an average of ten values measured at arbitrarypoints of the first base electrode 131 a and the second base electrode132 a on the first surface S1 and the second surface S2 of the ceramicbody 110. Since the thickness of the first base electrode 131 a and thesecond base electrode 132 a satisfy the above-range, it is possible toeffectively suppress the permeation of external moisture, or the like,while having excellent electrical characteristics.

In an embodiment of the present disclosure, the first and secondconductive layers 131 b and 132 b may be disposed to cover the firstbase electrode 131 a and the second base electrode 132 a. In the presentspecification, the conductive layers 131 b and 132 b are disposed tocover the base electrodes 131 a and 132 a, which may mean that theconductive layers 131 b and 132 b are disposed such that the baseelectrodes 131 a and 132 a are not exposed externally. As such, when theconductive layer is disposed to cover the base electrode, the moistureresistance reliability of the multilayer ceramic electronic componentaccording to the present disclosure may be improved.

In an embodiment of the present disclosure, the first and secondconductive layers 131 b and 132 b disposed on the first base electrode131 a and the second base electrode 132 a may be conductive resinlayers. The conductive resin layer may include a conductive metal andabase resin. The conductive resin layer may be formed using a conductivepaste for external electrodes including metal particles and a baseresin.

The conductive resin layer may include a conductive metal, and theconductive metal may be in a form of a powder particle. The shape of theconductive metal powder particle may be spherical or flake-shaped. Theconductive metal powder particles may be disposed to be in contact withor adjacent to each other in the conductive resin layer, and the baseresin may be disposed to surround the metal particles.

The conductive metal powder particle is not particularly limited as longas it is a particle of a metal having excellent conductivity, and mayinclude, for example, copper (Cu), silver (Ag), nickel (Ni), and alloysthereof.

The base resin may be a thermosetting resin. The thermosetting resin maybe an epoxy resin, but is not limited thereto.

The first and second conductive layers 131 b and 132 b disposed on thefirst base electrode 131 a and the second base electrode 132 a may beformed of a conductive resin layer, to protect the multilayer ceramicelectronic component from external thermal, chemical, and physicalimpacts, and increase bending strength of the multilayer ceramicelectronic component.

For example, the conductive resin layer may prevent moisture from beingpermeated into the ceramic body, and may prevent a plating solution frombeing permeated into the ceramic body when the plating layer is formed.Thereby, it is possible to improve the moisture resistance reliabilityof the multilayer ceramic electronic component according to the presentdisclosure.

In one example, a thickness of a first conductive layer 131 b and asecond conductive layer 132 b may be in a range of 3 μm to 13 μm. Thethickness of the first conductive layer 131 b and the second conductivelayer 132 b may refer to a length of the first conductive layer 131 band the second conductive layer 132 b in a first direction (the Xdirection). The thickness may be an average of ten values measured atarbitrary points of the first conductive layer 131 b and the secondconductive layer 132 b on the first surface S1 and the second surface S2of the ceramic body 110. Since the thicknesses of the first conductivelayer 131 b and the second conductive layer 132 b satisfy the aboveranges, permeation of external moisture, and the like can be effectivelysuppressed while having excellent electrical characteristics.

In an embodiment of the present disclosure, a thickness of the firstconductive layer 131 b and the second conductive layer 132 b measured inthe central portion of the first surface S1 and the second surface S2 ofthe ceramic body 110 is a and a thickness of the first conductive layer131 b and the second conductive layer 132 b measured at the end of thecapacitance formation portion is b, b/a may exceed 0.07. Referring toFIGS. 3 to 5 , the thickness ‘a’ of the first conductive layer 131 b andthe second conductive layer 132 b measured in the central portion of thefirst surface S1 and the second surface S2 of the ceramic body 110 maymean a length (D₂) of the first conductive layer 131 b and the secondconductive layer 132 b in a first direction (the X direction) in thecentral portion of the first surface S1 and the second surface S2 of theceramic body 110, as shown in FIGS. 3 and 5 . In addition, the thickness‘b’ of the first conductive layer 131 b and the second conductive layer132 b measured at the end of the capacitance formation portion may referto a length (D₁) of the first conductive layer 131 b and the secondconductive layer 132 b in a first direction (the X direction)in thecentral portion of the first surface S1 and the second surface S2 of theceramic body 110, as shown in FIGS. 3 and 5 .

The central portion of the first surface S1 and the second surface S2 ofthe ceramic body 110 may refer to a point in which two lines connectingopposite edges of the first surface S1 of the ceramic body 110 meet anda point in which two lines connecting opposite edges of the secondsurface S2 thereof meet. In addition, an end of the capacitanceformation portion may refer to a position of an internal electrodedisposed at an outermost portion of the first and second internalelectrodes 121 and 122 in a third direction (the Z direction), and mayrefer to a boundary between the internal electrode and the marginportion 112 of the ceramic body 110 in the second direction (the Ydirection). When the ratio (b/a) satisfies the above-described range, anexcellent corner coverage performance may be realized, and moistureresistance reliability may be improved.

In an embodiment of the present disclosure, a first terminal electrode131 c and a second terminal electrode 132 c may be disposed on the firstconductive layer 131 b and the second conductive layer 132 b of themultilayer ceramic electronic component, respectively. The firstterminal electrode 131 c and the second terminal electrode 132 c may bedisposed to cover the first conductive layer 131 b and the secondconductive layer 132 b, respectively. In the present specification,terminal electrodes 131 c and 132 c are disposed to cover conductivelayers 131 b and 132 b, which may mean that the terminal electrodes 131c and 132 c are disposed such that the conductive layers 131 b and 132 bare exposed externally, and it may mean a structure in which only thefirst terminal electrode 131 c and the second terminal electrode 132 care shown when the first conductive layer 131 b and the secondconductive layer 132 b are disposed, respectively, in the first externalelectrode 131 and the second external electrode 132, when viewed fromthe outside.

In an embodiment of the present disclosure, first and second terminalelectrodes 131 c and 132 c may be formed by plating. The first andsecond terminal electrodes 131 c and 132 c may be formed by sputteringor electric deposition, but are not limited thereto.

The first and second terminal electrodes 131 c and 132 c may contain themost nickel (Ni), but are not limited thereto, and may include nickel(Ni), copper (Cu), tin (Sn), palladium (Pd), platinum (Pt), gold (Au),silver (Ag), tungsten (W), titanium (Ti) or lead (Pb) and the like, oralloys thereof. The first and second terminal electrodes 131 c and 132 cmay be included to improve mountability, structural reliability,external durability, heat resistance, and/or equivalent seriesresistance (ESR) with a substrate.

In an example, a thickness of the first terminal electrode 131 c and thesecond terminal electrode 132 c may be in a range of 3 μm to 13 μm. Thethickness of the first terminal electrode 131 c and the second terminalelectrode 132 c may mean a length of the first terminal electrode 131 cand the second terminal electrode 132 c in a first direction (the Xdirection). The thickness may be an average of ten values measured atarbitrary points of the first terminal electrode 131 c and the secondterminal electrode 132 c on the first and second surfaces S1 and S2 ofthe ceramic body 110. Since the thickness of the first terminalelectrode 131 c and the second terminal electrode 132 c satisfy theabove range, permeation of external moisture, or the like, may beeffectively suppressed while having excellent electricalcharacteristics.

In an embodiment of the present disclosure, a plating layer P may beadditionally disposed on the first terminal electrode 131 c and thesecond terminal electrode 132 c, respectively. The plating layer P maycontain tin. When the first terminal electrode 131 c and the secondterminal electrode 132 c contain nickel, there is a problem that anoxide layer is formed on a surface of nickel during the firing process,such that it is difficult to forma plating layer. In addition, there isa problem that the formed plating layer may be easily peeled off. In themultilayer ceramic electronic component according to the presentembodiment, a uniform plating layer may be formed by disposing a platinglayer containing tin having excellent plating characteristics on thefirst terminal electrode 131 c and the second terminal electrode 132 ccontaining nickel.

According to an embodiment of the present disclosure, if a total lengthof a multilayer ceramic electronic component 100 in the first directionis less than 3.2 mm, a ratio (b/a) of the thickness ‘a’ of the firstconductive layer 131 b and the second conductive layer 132 b measured inthe central portion of the first surface S1 and the second surface S2 ofthe ceramic body 110 and the thickness ‘b’ of the first conductive layer131 b and the second conductive layer 132 b measured at the end of thecapacitance formation portion may be more than 0.2 but less than 1. Whenthe ratio (b/a) is 0.2 or less, moisture resistance reliability may belowered, and forming the first conductive layer 131 b and the secondconductive layer 132 b to exceed 1 may have a smaller gain that can besubstantially obtained in comparison with an excessive increase in cost.

According to another embodiment of the present disclosure, if a totallength of a multilayer ceramic electronic component 100 in the firstdirection is 3.2 mm or more, and a ratio (b/a) of the thickness ‘a’ ofthe first conductive layer 131 b and the second conductive layer 132 bmeasured in the central portion of the first surface S1 and the secondsurface S2 of the ceramic body 110 and the thickness ‘b’ of the firstconductive layer 131 b and the second conductive layer 132 b measured atthe end of the capacitance formation portion may be more than 0.07 butless than 1. When the ratio (b/a) is 0.07 or less, moisture resistancereliability may be lowered, and forming the first conductive layer 131 band the second conductive layer 132 b to exceed 1 may have a smallergain that can be substantially obtained may be substantially obtained incomparison with an excessive increase in cost.

Table 1 below shows results of a reliability test for moistureresistance with respect to a ratio (b/a) of the thickness ‘a’ of thefirst conductive layer 131 b and the second conductive layer 132 bmeasured in the central portion of the first surface S1 and the secondsurface S2 of the ceramic body 110 and the thickness ‘b’ of the firstconductive layer 131 b and the second conductive layer 132 b measured atthe end of the capacitance formation portion when the length of themultilayer ceramic electronic component is less than 3.2 mm.

Defects of the reliability for moisture resistance was investigated whena voltage of 2 Vr was applied for 48 hours at a temperature of 85° C.and a relative humidity of 85%, and the number of the multilayer ceramicelectronic components in which defects occurred in 400 samples wasinvestigated.

TABLE 1 Results of moisture resistance reliability 1608 2012 (length:1.6 mm, (length: 2.0 mm, b/a width: 0.8 mm) width 1.25 mm) Less than 0.13/400 2/400 Increase in Defects 0.1 or more~less 1/400 0/400 Increase inthan 0.2 Defects 0.2 or more~less 0/400 0/400 OK than 0.3 0.3 or more0/400 0/400 OK

As shown in Table 1, when a ratio (b/a) of the thickness ‘a’ of thefirst conductive layer 131 b and the second conductive layer 132 bmeasured in a central portion of the first conductive layer 131 b andthe second conductive layer 132 b and the thickness ‘b’ of the firstconductive layer 131 b and the second conductive layer 132 b measured atan end of the capacitance formation portion is less than 0.2, it may beconfirmed that the frequency of occurrence of defects increases.Therefore, when the ratio(b/a) is 0.2 or more, it can be confirmed thatit has excellent moisture resistance reliability.

Table 2 shows that results of a reliability test for moisture resistancewith respect to a ratio (b/a) of the thickness ‘a’ of the firstconductive layer 131 b and the second conductive layer 132 b measured inthe central portion of the first surface S1 and the second surface S2 ofthe ceramic body 110 and the thickness ‘b’ of the first conductive layer131 b and the second conductive layer 132 b measured at the end of thecapacitance formation portion when the length of the multilayer ceramicelectronic component is 3.2 mm or more.

TABLE 2 Results of moisture resistance reliability 3216 3225 (length:3.2 mm, (length: 3.2 mm, b/a width: 1.6 mm) width 2.5 mm) Less than 0.051/400 3/400 Increase in Defects 0.05 or more~less 1/400 2/400 Increasein than 0.07 Defects 0.07 or more~less 0/400 0/400 OK than 0.1 0.1 ormore 0/400 0/400 OK

As shown in Table 2, when a ratio (b/a) of the thickness ‘a’ of thefirst conductive layer 131 b and the second conducive layer 132 bmeasured in a central portion of the first surface S1 and the secondsurface S2 of the ceramic body 110 and the thickness ‘b’ of the firstconductive layer 131 b and the second conductive layer 132 b measured atan end of the capacitance formation portion is less than 0.07, it can beconfirmed that a defect occurrence frequency increases. Therefore, whenthe ratio (b/a) is 0.07 or more, it may be confirmed that it hasexcellent moisture resistance reliability.

As set forth above, according to an embodiment of the presentdisclosure, a multilayer ceramic electronic component capable ofimproving a corner coverage of an external electrode may be provided.

According to another embodiment of the present disclosure, a multilayerceramic electronic component having improved moisture resistancereliability may be provided.

However, various and advantageous advantages and effects of the presentdisclosure are not limited to the above description, and will be morereadily understood in the course of describing specific embodiments ofthe present disclosure.

While example embodiments have been shown and described above, it willbe apparent to those skilled in the art that modifications andvariations could be made without departing from the scope of the presentdisclosure as defined by the appended claims.

What is claimed is:
 1. A multilayer ceramic electronic component,comprising: a ceramic body including a capacitance formation portionincluding a dielectric layer and first and second internal electrodesstacked in a stacking direction with the dielectric layer interposedtherebetween, and including a first surface and a second surfaceopposing to each other in a first direction, a third surface and afourth surface opposing to each other in a second direction, and a fifthsurface and a sixth surface opposing to each other in a third directionwhich is the stacking direction; and first and second externalelectrodes disposed on the first and second surfaces of the ceramicbody, respectively, and including first and second base electrodesconnected to the first and second internal electrodes, first and secondconductive layers disposed to cover the first and second baseelectrodes, first and second terminal electrodes disposed on the firstand second conductive layers, and first and second plating layersdisposed on the first and second terminal electrodes, respectively,wherein a ratio ‘b/a’ is more than 0.2 but less than 1, where athickness of the first and second conductive layers in a respectivecentral portion of the first and second surfaces of the ceramic body is‘a’, and a thickness of the first and second conductive layers at arespective end of the capacitance formation portion is ‘b’, wherein thefirst and second conductive layers comprise a conductive metal and abase resin, wherein the first and second terminal electrodes containnickel, wherein the first and second plating layers contain tin.
 2. Themultilayer ceramic electronic component of claim 1, further comprising amargin portion disposed on both surfaces of the capacitance formationportion in the second direction; and a cover portion disposed on bothsurfaces of the capacitance formation portion in the third direction. 3.The multilayer ceramic electronic component of claim 2, the coverportion includes one or more dielectric layers.
 4. The multilayerceramic electronic component of claim 1, wherein the first and secondbase electrodes contain copper.
 5. The multilayer ceramic electroniccomponent of claim 1, wherein the first and second base electrodes havea thickness in a range of 3 μm to 13 μm.
 6. The multilayer ceramicelectronic component of claim 1, wherein the first and second conductivelayers have a thickness in a range of 3 μm to 13 μm.
 7. The multilayerceramic electronic component of claim 1, wherein the first and secondterminal electrodes have a thickness in a range of 3 μm to 13 μm.
 8. Themultilayer ceramic electronic component of claim 1, wherein a totallength of the multilayer ceramic electronic component in the firstdirection is less than 3.2 mm.
 9. A multilayer ceramic electroniccomponent, comprising: a ceramic body including a capacitance formationportion including a dielectric layer and first and second internalelectrodes stacked in a stacking direction with the dielectric layerinterposed therebetween, and including a first surface and a secondsurface opposing to each other in a first direction, a third surface anda fourth surface opposing to each other in a second direction, and afifth surface and a sixth surface opposing to each other in a thirddirection which is the stacking direction; and first and second externalelectrodes disposed on the first and second surfaces of the ceramicbody, respectively, and including first and second base electrodesconnected to the first and second internal electrodes and first andsecond conductive layers disposed to cover and being indirect physicalcontact with the first and second base electrodes, respectively, whereina ratio ‘b/a’ is more than 0.07 but less than 1, where a thickness ofthe first and second conductive layers in a respective central portionof the first and second surfaces of the ceramic body is ‘a’, and athickness of the first and second conductive layers at a respective endof the capacitance formation portion is ‘b’, wherein entire portions ofthe first and second base electrodes respectively disposed on the firstand second surfaces have a thickness in a range of 3 μm to 13 μm, orentire portions of the first and second conductive layers respectivelydisposed on the first and second surfaces have a thickness in a range of3 μm to 13 μm.
 10. The multilayer ceramic electronic component of claim9, further comprising a margin portion disposed on both surfaces of thecapacitance formation portion in the second direction; and a coverportion disposed on both surfaces of the capacitance formation portionin the third direction.
 11. The multilayer ceramic electronic componentof claim 10, the cover portion includes one or more dielectric layers.12. The multilayer ceramic electronic component of claim 9, wherein thefirst and second base electrodes contain copper.
 13. The multilayerceramic electronic component of claim 9, wherein the first and secondconductive layers comprise a conductive metal and a base resin.
 14. Themultilayer ceramic electronic component of claim 9, wherein first andsecond terminal electrodes are additionally disposed on the first andsecond conductive layers, respectively.
 15. The multilayer ceramicelectronic component of claim 14, wherein the first and second terminalelectrodes have a thickness in a range of 3 μm to 13 μm.
 16. Themultilayer ceramic electronic component of claim 14, wherein the firstand second terminal electrodes contain nickel.
 17. The multilayerceramic electronic component of claim 14, wherein a plating layer isadditionally disposed on each of the first and second terminalelectrodes.
 18. The multilayer ceramic electronic component of claim 17,wherein the plating layer contains tin.
 19. The multilayer ceramicelectronic component of claim 9, wherein a total length of themultilayer ceramic electronic component in the first direction is 3.2 mmor more.